1. Field of the Invention
The present invention relates to cosmetic temporary coloring compositions which contain, as an active ingredient, at least one protein derivative which contains residues of molecules of dye grafted onto the protein chain. "Molecules of dye" as used herein refers to molecules which contain chromophoric or chromogenic groups. The coloring compositions of the invention may be used to color keratinous supports, such as keratin fibers, and, in particular, human hair, or may be applied to the surface of the skin.
2. Description of the Prior Art
Colored protein derivatives have been described in the literature, but they have never been proposed as active ingredients in cosmetic temporary coloring compositions. French Patent No. 1,310,583 describes substances obtained by grafting molecules of dye onto proteins, especially onto casein, these substances being used for permanently coloring viscose masses, as pigments or for dyeing synthetic resins.
Many protein hydrolyzates are known which have useful properties for treating the skin surface, or hair. It is known, furthermore, how to graft residues of molecules of dye onto chains of synthetic polymers. These grafted synthetic polymers can be used to produce coloring compositions; however, these polymers are generally only sparingly soluble in common cosmetic solvents, and they form films which are excessively rigid.